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    <title>Document</title>
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<body>
    <script>
        function fn(str) {
            var str1 = str.slice(0, 1).toUpperCase() + str.slice(1).toLowerCase()
            var str2 = str1.split("").reverse().join('').replace(/\s*/g,"");
            console.log(str2.replace('!', '啊'));
        }
        fn('hello world 我爱你 !')


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